Searches time out when they take too long to find results. As a gold member, you have a longer limit than ordinary users, but sometimes searches will still take longer than that.
Sometimes you can make a search faster by adding order:score
to the search terms (it causes the database to use a different way of searching, which can be faster), or by changing the number of results per page with the limit:
metatag (for example, limit:10
or limit:50
-- in the past, some searches have been faster with fewer results per page, and some with more results per page.)
Could you give an example of a search that isn't working?